Bernard J. Hudson

Plasmodium knowlesi in Human, Indonesian Borneo

Plasmodium knowlesi is now established as the fifth Plasmodium species to cause malaria in humans. We describe a case of P. knowlesi infection acquired in Indonesian Borneo that was imported into Australia. Clinicians need to consider this diagnosis in a patient who has acquired malaria in forest areas of Southeast Asia.

Low rate of Propionibacterium acnes in arthritic shoulders undergoing primary total shoulder replacement surgery using a strict specimen collection technique

BACKGROUND Propionibacterium acnes is a recognized pathogen in postoperative shoulder infections. A recent study reported growth of P acnes in 42% of glenohumeral joints in primary shoulder arthroplasty, concluding that P acnes may cause shoulder osteoarthritis. Whether these results reflect true bacterial infection or specimen contamination is unclear. Our prospective study aimed to determine the rate of P acnes infection in arthritic shoulders using a strict specimen collection technique. METHODS We used modified Oxford protocol to collect tissue specimens from the glenohumeral joint of 32 consecutive patients undergoing primary shoulder arthroplasty. Specimens were cultured specifically for P acnes. Diagnosis of P acnes infection required 2 or more positive cultures and histopathology compatible with infection. RESULTS Three of 32 patients had a positive culture for P acnes. Overall, 3.125% of specimens grew P acnes without histologic evidence of infection. There were no patients with P acnes infection. The difference in culture rates between patients with idiopathic osteoarthritis and those with a predisposing cause for osteoarthritis was not significant. CONCLUSIONS We found a low rate of positive cultures for P acnes, but no P acnes infection and no difference between types of osteoarthritis. These results do not support a cause-and-effect relationship between P acnes and osteoarthritis. The differing results from previous studies are likely explained by our strict specimen collection technique, reflecting different rates of contamination rather than infection. That P acnes contamination occurs in primary shoulder arthroplasty is concerning. Further studies are needed to assess the rates of contamination in shoulder surgery, its clinical effect, and to determine optimal antibiotic prophylaxis.

Phaeohyphomycotic Soft Tissue Infections Caused by the Coelomycetous Fungus Microsphaeropsis arundinis

ABSTRACT Microsphaeropsis arundinis is an anamorphic fungal plant inhabitant belonging to the form class Coelomycetes. We describe two cases of M. arundinis soft tissue infections in immunosuppressed patients. This organism has not previously been described as causing disease in humans. It was identified on the basis of its typical ostiolate pycnidial conidiomata, ampulliform conidiogenous cells, and small, smooth-walled, brown, cylindrical conidia.

Genomic islands 1 and 2 play key roles in the evolution of extensively drug-resistant ST235 isolates of Pseudomonas aeruginosa

Pseudomonas aeruginosa are noscomially acquired, opportunistic pathogens that pose a major threat to the health of burns patients and the immunocompromised. We sequenced the genomes of P. aeruginosa isolates RNS_PA1, RNS_PA46 and RNS_PAE05, which displayed resistance to almost all frontline antibiotics, including gentamicin, piperacillin, timentin, meropenem, ceftazidime and colistin. We provide evidence that the isolates are representatives of P. aeruginosa sequence type (ST) 235 and carry Tn6162 and Tn6163 in genomic islands 1 (GI1) and 2 (GI2), respectively. GI1 disrupts the endA gene at precisely the same chromosomal location as in P. aeruginosa strain VR-143/97, of unknown ST, creating an identical CA direct repeat. The class 1 integron associated with Tn6163 in GI2 carries a blaGES-5–aacA4–gcuE15–aphA15 cassette array conferring resistance to carbapenems and aminoglycosides. GI2 is flanked by a 12 nt direct repeat motif, abuts a tRNA-gly gene, and encodes proteins with putative roles in integration, conjugative transfer as well as integrative conjugative element-specific proteins. This suggests that GI2 may have evolved from a novel integrative conjugative element. Our data provide further support to the hypothesis that genomic islands play an important role in de novo evolution of multiple antibiotic resistance phenotypes in P. aeruginosa.

Infectious arthritis of the knee caused by Mycobacterium terrae: a case report.

Mycobacterium terrae is ubiquitous in our environment. M terrae infections most commonly involve tendon sheaths, bones, bursae, and joints. We report a case of infectious arthritis of the knee caused by M terrae in a 21-year-old man who had non-specific chronic synovitis. No organism was seen on microscopy or isolated from cultures until months later. Initially the M terrae culture was considered a contaminant and specific anti-mycobacterial treatment was not advised. The patient was commenced on suppressive therapy for persistent effusion and discomfort. Eventually, the M terrae infection was confirmed and he was commenced on clarithromycin, ciprofloxacin, and ethambutol. The triple antibiotic regimen was continued for 2 years. The knee improved but never completely settled. The patient chose to cease all antibiotic medication. The knee remained swollen and irritable, with little chance of eradicating the organism.

A Randomised Comparative Study of Once-Daily Ceftriaxone and 6-Hourly Flucloxacillin in the Treatment of Moderate to Severe Cellulitis

SummaryIn a study comparing flucloxacillin (1g every 6 hours intravenously), as standard treatment for moderate to severe cellulitis, with ceftriaxone (1g once daily intravenously), ceftriaxone was found to be an effective alternative to flucloxacillin without the associated risk of serious cholestatic hepatitis.Forty-seven evaluable patients, 24 in the ceftriaxone group and 23 in the flucloxacillin group, were evaluated in this prospective randomised study examining clinical efficacy, safety and duration of hospitalisation. 22 of 23 (96%) patients in the ceftriaxone group achieved clinical success (clinical cure and improvement), while 16 of 22 (70%) flucloxacillin patients were considered a clinical success (clinical cure and improvement). Baseline bacteriology was not performed in the single patient who did not respond to ceftriaxone, while 5 of the 6 patients who did not respond to flucloxacillin had a negative baseline culture. The remaining flucloxacillin failure was infected with Staphylococcus aureus, which persisted at the post-treatment evaluation. All other pathogens isolated at baseline in both treatment arms were eradicated at the post-treatment bacteriological evaluation.No serious or unexpected adverse events were reported in either group. Because it requires only once-daily administration, ceftriaxone made it possible for some patients to be treated as outpatients, resulting in an average reduction of 3.04 hospital bed-days, while at the same time being as efficacious as flucloxacillin.

A case of carbapenemase-producing Klebsiella pneumoniae in Australia

Sir, A 64-year-old man was hospitalised during a holiday in Greece and on return was admitted to a Sydney hospital. An open lung biopsy confirmed Mycobacterium tuberculosis. The patient later presented with an aorto-oesophageal fistula which required emergency stenting. Following radical aortic resection the patient developed sepsis and died. Operative specimens grew Klebsiella resistant to meropenem. The isolate tested positive for a Klebsiella pneumoniae carbapenemase (KPC). This case is the first known isolation of a KPC-producing organism from an Australian hospital. In December 2008, the patient was hospitalised for recurrent epididymo-orchitis. He was noted to be hypotensive and Synacthen stimulation testing confirmed the diagnosis of Addison’s disease. Computed tomography (CT) scanning of the chest, abdomen and pelvis showed left-sided adrenal calcification and an 8 mm saccular thoracic aortic aneurysm with luminal ulceration proximal to the aneurysm. These changes were thought to be in keeping with atherosclerotic disease. The patient underwent elective percutaneous endoluminal stent insertion in July 2009. Two months later the patient travelled to Greece. He was unwell during the holiday and was twice admitted to Greek hospitals, including an admission to an intensive care unit (ICU). The discharge diagnosis was ‘Addisonian crisis’ but the inciting event was unclear. In October 2009, 2 weeks after returning to Australia, the patient remained unwell and was admitted to our institution for the first time with fevers, lethargy, anorexia and breathlessness. CT scans of the chest showed bilateral, symmetrical, peri-hilar, ground-glass infiltrates. Given the history of recent travel and the outbreak of H1N1 influenza at the time, a presumptive diagnosis of influenza pneumonitis was made. He was intubated, ventilated and treated with oseltamivir. Vancomycin, meropenem and azithromycin were added to cover hospital-acquired and atypical pathogens. Although the patient showed early improvement, his fevers persisted and he required re-intubation and re-admission to ICU on three further occasions. The radiological changes progressed to more confluent consolidation. After several weeks in hospital with poor response to broad-spectrum antimicrobial therapy, an open lung biopsy was performed. Pathology showed multiple caseating granulomas with numerous acid fast bacilli. The patient was commenced on standard four drug therapy with rifampicin, isoniazid, pyrazinamide and ethambutol. Culture of tissue subsequently grew pan-susceptible Mycobacterium tuberculosis. The patient was discharged to a rehabilitation facility, but was re-admitted 4 weeks later with persistent fever, anorexia and weight loss, despite therapy. He had developed a recurrent pleural effusion with consolidation of the left lower lobe. Diagnostic thoracocentesis showed 2þ acid fast bacilli on smear, but mycobacterial culture remained sterile. The patient was again discharged home to continue his anti-tuberculous therapy.

Bacterial Communities Vary between Sinuses in Chronic Rhinosinusitis Patients.

Chronic rhinosinusitis (CRS) is a common and potentially debilitating disease characterized by inflammation of the sinus mucosa for longer than 12 weeks. Bacterial colonization of the sinuses and its role in the pathogenesis of this disease is an ongoing area of research. Recent advances in culture-independent molecular techniques for bacterial identification have the potential to provide a more accurate and complete assessment of the sinus microbiome, however there is little concordance in results between studies, possibly due to differences in the sampling location and techniques. This study aimed to determine whether the microbial communities from one sinus could be considered representative of all sinuses, and examine differences between two commonly used methods for sample collection, swabs, and tissue biopsies. High-throughput DNA sequencing of the bacterial 16S rRNA gene was applied to both swab and tissue samples from multiple sinuses of 19 patients undergoing surgery for treatment of CRS. Results from swabs and tissue biopsies showed a high degree of similarity, indicating that swabbing is sufficient to recover the microbial community from the sinuses. Microbial communities from different sinuses within individual patients differed to varying degrees, demonstrating that it is possible for distinct microbiomes to exist simultaneously in different sinuses of the same patient. The sequencing results correlated well with culture-based pathogen identification conducted in parallel, although the culturing missed many species detected by sequencing. This finding has implications for future research into the sinus microbiome, which should take this heterogeneity into account by sampling patients from more than one sinus.

Inflammatory eye disease: Pre-treatment assessment of patients prior to commencing immunosuppressive and biologic therapy: Recommendations from an expert committee

AIM To outline recommendations from an expert committee on the assessment and investigation of patients with severe inflammatory eye disease commencing immunosuppressive and/or biologic therapy. METHOD The approach to assessment is based on the clinical experience of an expert committee and a review of the literature with regard to corticosteroids, immunosuppressive drug and biologic therapy and other adjunct therapy in the management of patients with severe sight-threatening inflammatory eye disease. CONCLUSION We recommend a careful assessment and consultative approach by ophthalmologists or physicians experienced in the use of immunosuppressive agents for all patients commencing immunosuppressive and/or biologic therapy for sight threatening inflammatory eye disease with the aim of preventing infection, cardiovascular, metabolic and bone disease and reducing iatrogenic side effects.

Colletotrichum gloeosporioides sensu lato causing deep soft tissue mycosis following a penetrating injury

Colletotrichum species have been rarely implicated in human disease. We describe a case of deep soft tissue mycosis following a penetrating injury with a lemon tree thorn. Direct Blankophor BA (Bayer) stain from intraoperative tissue showed fungal elements. Pure growth fungus was apparent at 2-4 days. Morphological features provisionally identified the isolate as a coelomycetous fungus, likely Colletotrichum species. This was confirmed with molecular analysis of the internal transcribed spacer region (ITS) region.